RESUMO
To reduce the high mortality rates caused by ovarian cancer, creating high-sensitivity, quick, basic, and inexpensive methods for following cancer antigen 125 (CA-125) levels in blood tests is of extraordinary significance. CA-125 is known as the exclusive glycoprotein employed in clinical examinations to monitor and diagnose ovarian cancer and detect its relapses as a tumor marker. Elevated concentrations of this antigen are linked to the occurrence of ovarian cancer. Herein, we designed organohydrogels (ONOHs) for identifying the level of CA-125 antigen at fast and high sensitivity with electrochemical strategies in a serum medium. The ONOH structures are synthesized with glycerol, agar, and glutaraldehyde and at distinct ratios of onion oil, and then, the ONOHs are characterized with Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Electrochemical measurements are performed by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) in the absence and presence of CA-125 on the designed ONOHs. For the prepared ONOH-3 electrode, two distinct linear ranges are determined as 0.41-8.3 and 8.3-249.0 U/mL. The limit of quantitation and limit of detection values are calculated as 2.415 and 0.805 µU/mL, respectively, (S/N = 3). These results prove that the developed electrode material has high sensitivity, stability, and selectivity for the detection of the CA-125 antigen. In addition, this study can be reasonable for the practical detection of CA125 in serum, permitting early cancer diagnostics and convenient treatment.
RESUMO
In the present study, the effect of methidathion, cypermethrin, and deltamethrin pesticides on Lake Van fish (Chalcalburnus tarichii Pallas, 1811) liver 6-phosphogluconate dehydrogenase enzyme activity was investigated due to the fact that these pesticides are extensively used to improve agricultural productivity in the Van region. 2',5'-ADP Sepharose 4B affinity chromatography was used to purify 6-phosphogluconate dehydrogenase enzyme from fish liver and SDS-PAGE technique was used to control the purity of this enzyme. The in vitro effect of methidathion, cypermethrin, and deltamethrin pesticides on the enzyme activity was investigated. The enzyme was purified 1,050-fold with specific activity of 27.04 EU/mg protein. Moreover, Ki constants of methidathion, cypermethrin, and deltamethrin were to be 3.294 ± 0.215, 0.718 ± 0.095, and 0.084 ± 0.009 mM respectively. The IC50 value were estimated as 9.95 × 10(-5) ± 0.1844 × 10(-5) mM for methidathion, 1.01 × 10(-4) ± 0.01413 × 10(-4) mM for cypermethrin, and 4.43 × 10(-6) ± 0.05653 × 10(-6) mM for deltamethrin. In conclusion, deltamethrin inhibits the enzyme activity more than methidathion and cypermethrin.
Assuntos
Cyprinidae/metabolismo , Fígado/enzimologia , Praguicidas/toxicidade , Fosfogluconato Desidrogenase/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Lagos , Fígado/efeitos dos fármacos , Nitrilas/toxicidade , Compostos Organotiofosforados/toxicidade , Piretrinas/toxicidadeRESUMO
In this study, the carbon nanotube supported gold, bismuth, and gold-bismuth(Au/MWCNT, Bi/MWCNT, and Au-Bi/MWCNT) nanocatalysts were prepared with NaBH4 reduction method at varying molar atomic ratio for glucose electrooxidation (GAEO). The synthesized nanocatalysts at different Au: Bi atomic ratios are characterized via x - ray diffraction (XRD), transmission electron microscopy (TEM), and N2 adsorption-desorption. For the performance of AuBi/MWCNT for GAEO, electrochemical measurements are performed by using different electrochemical techniques namely cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS). Monometallic Au/MWCNT exhibits higher activity than Bi/MWCNT with 256.57 mA/mg (0.936 mA/cm2) current density. According to CV results, Au80Bi20/MWCNT nanocatalyst has the highest GAEO activity with the mass activity of 320.15 mA/mg (1.133 mA/cm2). For Au80Bi20/MWCNT, central composite design (CCD) is utilized for optimum conditions of the electrode preparation. Au80Bi20/MWCNT nanocatalysts are promising anode nanocatalysts for direct glucose fuel cells (DGFCs).
RESUMO
Coronavirus, known as the coronavirus pandemic, is continuing its spread across the world, with over 42 million confirmed cases in 189 countries and more than 1.15 million deaths. Although, scientists focus on the finding novel drugs and vaccine for SARS-CoV-2, there is no certain treatment for it. Antiviral drugs such as; oseltamivir, favipiravir, umifenovir, lopinavir, remdesivir, hydroxychloroquine, chloroquine, azithromycin, ascorbic acid, corticosteroids, are mostly used for patients. They prevent cytokine storm that is the main reason of deaths related to SARS-CoV-2. In addition, anti-inflammatory agents have critical roles to inhibit the lung injury and multisystem organ dysfunction. The combination with anti-viral drugs with other drugs displays high synergistic effects. In the present study, the drugs used for Covid-19 are analyzed and compare the efficiency for the Covid-19 patients from the different continents including USA, South Korea, Italy, Spain, Germany, Russia, Brazil, Turkey, and China. Nowadays, all countries tried to find vaccine and new drug candidates for SARS-CoV-2, but anti-viral drugs may be the best candidates for the treatment of Covid-19 before finding novel anti-Covid drug.
Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Antivirais/química , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Resultado do TratamentoRESUMO
In the present study, the carbon supported Pd, PdAg and PdAgNi (Pd/C, PdAg/C and PdAgNi/C) electrocatalysts are prepared via NaBH4 reduction method at varying molar atomic ratio for formic acid electrooxidation. These as-prepared electrocatalysts are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma mass spectrometry (ICP-MS), N2 adsorption-desorption, and X-ray electron spectroscopy (XPS), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), chronoamperometry (CA), and lineer sweep voltammetry (LSV). While Pd50Ag50/C exhibits the highest catalytic activity among the bimetallic electrocatalyst, it is observed that Pd70Ag20Ni10/C electrocatalysts have the best performance among the all electrocatalysts. Its maximum current density is about 1.92 times higher than that of Pd/C (0.675â¯mAâ¯cm-2). Also, electrochemical impedance spectroscopy (EIS), chronoamperometry (CA) and lineer sweep voltammetry (LSV) results are in a good agreement with CV results in terms of stability and electrocatalytic activity of Pd50Ag50/C and Pd70Ag20Ni10/C. The Pd70Ag20Ni10/C catalyst is believed to be a promising anode catalyst for the direct formic acid fuel cell.
RESUMO
At present, commercial pure Titanium (Ti) and microstructured pre-alloyed Titanium-Nickel (TiNi) powders are employed as a sensitive electrochemical hydrogen peroxide (H2O2) sensor. Surface characterization of these materials are performed by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical characterization is achieved via cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) on Ti and TiNi modified glassy carbon electrode (GCE). The electrochemical behavior of H2O2 at the pure Ti/GCE and microstructure pre-alloyed TiNi/GCE are studied by CV in 0.1â¯M phosphate buffer solution (PBS) containing as the supporting electrolyte. In addition, CA is employed for the determination of H2O2 at the applied potential of 0â¯V vs. Ag/AgCl. The sensor has a linear response range of 0.5-17.5â¯mM with a sensitivity of 280⯵Aâ¯mM-1â¯cm-2. Moreover, the limit of detection (LOD) and limit of quantification (LOQ) are 0.5⯵M and 1.7⯵M, respectively. The electrochemical sensor exhibits fast and selective responses to H2O2 concentration. The applicability of the sensor is checked using a hair coloring as a real sample with satisfactory results.